package com.qy.base.utils;


import com.qy.base.core.Constants;

import java.io.*;
import java.net.HttpURLConnection;
import java.net.URL;
import java.text.SimpleDateFormat;
import java.util.Date;
import java.util.UUID;

public class DownLoadImgFromNet {

    public static String downloadImg(String imgPath) throws Exception {
//new一个URL对象 
        URL url = new URL(imgPath);
//打开链接 
        HttpURLConnection conn = (HttpURLConnection) url.openConnection();
//设置请求方式为"GET" 
        conn.setRequestMethod("GET");
//超时响应时间为5秒 
        conn.setConnectTimeout(5 * 1000);
//通过输入流获取图片数据 
        InputStream inStream = conn.getInputStream();
//得到图片的二进制数据，以二进制封装得到数据，具有通用性 
        byte[] data = readInputStream(inStream);
//new一个文件对象用来保存图片，默认保存当前工程根目录
        // 生成文件名
        String randomName = UUID.randomUUID().toString() + ".png";
        String imageName = getDate() + "/" + randomName;
        //服务器真正存放的路径
        String fileName = Constants.PATH_IMAGE_PATH + imageName;
        // 保存图片到本地
        File file = new File(fileName);
        if (!file.getParentFile().exists()) {
            file.getParentFile().mkdirs();
        }
        OutputStream out = new FileOutputStream(fileName);
        out.write(data);
        out.flush();
        out.close();
        return Constants.PATH_IMAGE_PATH_DB + imageName;
    }

    public static byte[] readInputStream(InputStream inStream) throws Exception {
        ByteArrayOutputStream outStream = new ByteArrayOutputStream();
//创建一个Buffer字符串 
        byte[] buffer = new byte[1024];
//每次读取的字符串长度，如果为-1，代表全部读取完毕 
        int len = 0;
//使用一个输入流从buffer里把数据读取出来 
        while ((len = inStream.read(buffer)) != -1) {
//用输出流往buffer里写入数据，中间参数代表从哪个位置开始读，len代表读取的长度 
            outStream.write(buffer, 0, len);
        }
//关闭输入流 
        inStream.close();
//把outStream里的数据写入内存 
        return outStream.toByteArray();
    }
    protected static String getDate() {
        Date currentTime = new Date();
        SimpleDateFormat simpleDateFormat = new SimpleDateFormat("yyyyMMdd");
        return simpleDateFormat.format(currentTime);
    }
}
